Why can baked goods like cookies and cake be left out on the counter that contain eggs, but scrambled or fried eggs would need to be refrigerated?

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Why can baked goods like cookies and cake be left out on the counter that contain eggs, but scrambled or fried eggs would need to be refrigerated?

In: Other

Many factors are considered for food spoilage, but for this example, I give you the two main reasons:

1. Baking food kills a lot of microbes that can cause the food to spoil. So they stay good for longer.
2. In chemistry, there is a term called Activity of Water or Water Activity *(aw)* which basically means how much water is available for the microbes to use. Cooking and baking reduces the *aw* and helps the food stay good for longer. For example, when you make jam out of cherries and add a lot of sugar, the sugar reduces the aw. That’s why jams stay good for long periods of time.

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Edit:

1. Thank you for the upvotes and awards. Please also award the OP themself, since a good question is more valuable than a good answer.
2. Water Activity is mostly influenced by osmolarity, which basically means how many particles are in the water. These particles can be anything, sugar molecules, Na and Cl ions (from salt), etc. So food does not have to be dry to have low water activity necessarily. If you add too many particles to food (A lot of sugar or a lot of salt), then water activity is reduced. Although, adding not enough sugar might actually make it spoil faster since it is a good food source for many microbes.

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It’s the water content. Water is life, also for bacteria. Plus, sugar is a natural preservative.

It’s the water content. Water is life, also for bacteria. Plus, sugar is a natural preservative.

As others have mentioned, it’s all about water.

You’ll notice that eggs that haven’t been baked can still be left in the shelf, provided they’ve had their water content reduced.

For example, powdered eggs, certain types of meringue or dried pasta.

So cookies can sit out for two weeks (and more); cooked eggs can only sit out for two hours. They are both “cooked”, right? Yes and no.

The cookies are made with sugar and some salt. They are also dried in an oven. The moisture in them is evaporated or locked up in the sugar and salt. Without ‘free’ moisture, it is hard for the bacteria to get going.

The eggs are all protein. The cooking changes the structure of the protein and dries it out some (or a lot if you cook the hell out of it), but most eggs still have some moisture. And they don’t have anything to lock up that moisture and keep it away from bacteria. So instead it provides a whole bunch of food + moisture for the bacteria to use to grow upon. If you leave the eggs out for two hours and come back to it, you’ll see that it has started to “sweat” somewhat, and that moisture provides a great home for bacteria.

Fun fact: you can let an egg sit out a very long time…by salting it. You can crack an egg yolk into salt and then cover it in more salt and it will preserve it. Eventually, a good bacteria shows up and it results in lactic acid on the egg, which preserves it.

Also, there are dried eggs – they are dried very quickly in industrial dryers and become “powdered egg” and can last 5 year.

Scrambled and fried eggs are only considered “loosely cooked” whereas baked goods with egg in are “well cooked”. Many people with egg allergy can tolerate well cooked egg but not loosely cooked egg – this is common in children (mostly they will “grow out of” the egg allergy).

Edited to add – my daughter (8 months) has an egg allergy. She tolerates well cooked egg but “loosely cooked” egg gives her a horrendous rash and triggers her eczema. I think the proteins change with cooking. The allergy clinic provide a list of well cooked/loosely cooked foods so you know what to give/avoid.

Too many of these explanations are over-5. Here:

* If people were on a planet where everything was made of cake, you would be too thirsty, and every bite would just make you thirstier as you struggle to swallow.
* If people were on a planet where everything was made of scrambled-eggs, you could squeeze out enough water to drink sometimes.
* So the scrambled-eggs planet is easier to build a civilization on.

We leave scrambled or fried eggs out for a day and still eat, yummy! Perhaps it depends on the climate you live in?

In addition to the Activity of Water, there is the idea that we in North America are for too cautious. Almost every sealed (moist) food we buy says ‘refrigerate after opening’ , yet the same things in Europe stay out on a shelf. European fridges are sometimes so small, only things they *prefer* to be cold are stored in them… like their beer. I will no doubt be corrected on this… there *are* items that are *not* beer that need to go in the fridge in Europe…

I was shocked when I volunteered to work in a kitchen at a wilderness camp for a week (in North America) and all of the condiments were stored outside of the fridge. I asked how that was even legal, since food handling laws were so specific about things like that. I was told that mayo, ketchup, mustard, didn’t have to be refrigerated. They had to take condiments *out* with a clean spoon, and were not allowed to put leftovers back *in*, but they *were* allowed be stored in a ‘cool dry place’, even after opening. It said right on the plastic jugs ‘Refrigerate after opening’ but I guess that’s more of a suggestion. If you *have* to ask, then yes, store it in a fridge.

In a lot of countries they don’t even refrigerate eggs. You buy them on the shelves at the grocery store

baked goods are relatively dry and thoroughly cooked by nature, whereas pan fried goods are cooked pretty shortly and kept pretty moist throughout. overall, pretty good environment for egg-hunting-microbes. also, scrambled and fried eggs are both, as the name suggests, almost entirely egg, so if the egg part of those dishes go bad, you’re a lot more likely to notice and have a bad time.